The present invention relates to a safety switch operating mechanism.
Safety switches are well known, and are typically used to prevent access to for example dangerous electromechanical machinery when that machinery is in operation. In an conventional arrangement the safety switch is mounted on a door post of a machinery guard, and an actuator for the safety switch is mounted on a corresponding door. When the door is closed the actuator engages with the safety switch, which in turn closes an electrical contact that allows power to be supplied to the machinery. This arrangement ensures that power can only be supplied to the machinery when the guard door is shut. When the guard door is opened, the actuator disengages from the safety switch, thereby opening the electrical contact and cutting off the supply of power to the machinery.
In some instances a problem has arisen in that an operating mechanism of the safety switch may allow an actuator to be too easily removable from the safety switch. In one situation, vibration of the electromechanical machinery may be sufficient to cause the actuator to jump out of the safety switch, allowing the door to swing open and interrupting the supply of power to the electromechanical machinery. Since this immediately interrupts operation of the electromechanical machinery, it will be appreciated that it reduces the efficiency of the operation of the machinery. An engineer or other operator must close the door of the housing, so that the actuator engages with the safety switch, thereby allowing power to be supplied to the electromechanical machinery before it can resume operation.
The present invention is directed to overcome or substantially mitigate the above disadvantage.